Suppose I could get the Rotel RB-1070(130x2) for $400 and the Rotel RB 1080(200x2) for $675-$700 used. Would the 1080 be worth the extra $275 for the extra 70 watts?

They're both well within my budget. I've acquired some money to put where my mouth is, so I may be buying soon. I'm set on Axioms, and still looking around for the rest of the setup.

I wouldn't be in a huge room(12x10, I think). I listen to a large variety of music, yet my usual is heavy metal such as Dream Theater, Tool, Led Zeppelin, and I like blasting it. some of the DT stuff does a good job of destroying those wimpy 10000 watt lightshow systems in best buy.

This would be IT until I added a used HSU or SVS sub into the mix. I don't want to have to worry about clipping when the peaks of the music come as I'm blasting it. I understand that doubling the wattage only increases things by 3 dB. Since the wattage is not twice as loud but one and a half times as loud, I'd assume the volume difference between the two would be a barely noticeable 1.5 dB, yet I just want to make sure.

Thanks.